This Non-provisional application claims priority under 35 U.S.C. §119(a) on Patent Application No(s). 095111461 filed in Taiwan, Republic of China on Mar. 31, 2006, the entire contents of which are hereby incorporated by reference.
1. Field of Invention
The invention relates to a control device and a setting method thereof, in particular, to a motor control device and a setting method thereof.
2. Related Art
Motors have been applied to various electric devices such as electric fans. To maintain the efficiency of the motor, the revolution speed of motor must be controlled and maintained accurately.
As shown in FIG. 1, a conventional control device of a motor includes a controller 10, a converter 14 and a revolution speed measuring device 15. The controller 10 includes an analogue to digital converting (ADC) unit 11, a recording unit 12 and a processing unit 13. The controller 10 controls the operation of a motor 2. The converter 14 converts an externally inputted revolution speed control signal 141, which is a pulse width modulation signal, to a voltage signal 111. The analogue to digital converting unit 11 measures the voltage signal 111 and generates a voltage value 112.
The recording unit 12 presets a revolution speed table 120. The revolution speed table 120 records a plurality of voltage values 121 and a plurality of motor revolution speed values 122 corresponding to the voltage values 121. Thus, the processing unit 13 selects the corresponding voltage value 121 from the revolution speed table 120 according to the measured voltage value 112, and then selects the corresponding motor revolution speed value 122 according to the selected voltage value 121. The processing unit 13 generates a driving current 131 according to the motor revolution speed value 122 so as to drive the motor 2. Additionally, the revolution speed measuring device 15 measures the revolution speed of the motor 2. The processing unit 13 feedback controls the driving current 131 according to the revolution speed of the motor 2, such that the revolution speed of the motor 2 controlled based on the set revolution speed value 122.
Since the revolution speed table 120 is stored in the recording unit 12 previously when the motor 2 is manufactured, and the recording unit 12 is a read only memory, the revolution speed table 120 cannot be modified. Therefore, if the environment of the control device 1 is changed (e.g. by temperature increase or decrease) or if the actual operating values of the internal mechanical elements are different from the specifications, the voltage signal 111 generated by the converter 14 or by the analogue to digital converting unit 11, and/or the voltage value 112 are not equal to the predetermined operating values by a user. For instance, the highest value of the revolution speed control signal 141 originally let the motor 2 operate at the highest speed. However, if the output voltage signal 111 is inaccuracy due to the internal mechanism element of the converter 14, the voltage value 112 read by the revolution speed table may be inaccuracy and thus not corresponded to the highest revolution speed.
Thus, if the revolution speed table in each control device could be set in consideration of possible deviations during the production, all contents in the revolution speed table would satisfy the input/output needs of the clients. Thus, it is an important subjective to provide a control device and a setting method for a motor that can calibrate and adapt to the possible practical operating environment, and further, to control the motor revolution speed precisely and promote the operating efficiency of the motor.